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Bats types AU

Despite the name, not all Megabats (megachiroptera) are larger than Microbats (microchiroptera). The major distinction between the two suborders is based on other factors.

Megabats eat fruit, pollen, or nectar. They have a well-developed visual cortex and shows good visual acuity. Also, the sense of smell is excellent in these creatures. In contrast to Microbats, Megabats do not, as a rule, use echolocation (with one exception, the Egyptian fruit bat, which uses high pitched clicks to navigate in caves).

Microbats use echolocation, whereas Megabats do not (except for Rousettus and relatives).

Microbats lack the claw at the second toe of the forelimb.

The ears of Microbats do not form a closed ring, but the edges are separated from each other at the base of the ear.

Microbats lack under fur; they only have guard hairs or are naked.

Microbats eat insects, blood, small mammals, and fish.

Bats are mammals which give birth to live young and produce milk to feed them. Over sixty different kinds occur in Australia. Most eat insects, but eight feed only on flowers and fruit, and are known as fruit-bats or flying-foxes. Four of these are amongst the world's largest bats (links to pictures of these are provided below). They may weigh up to one kilogram and their wings may span more than a metre. Because they are large and can fly long distances they can cause considerable damage to cultivated fruit. There are several other kinds which are much smaller animals and are rarely a problem.

The preferred food of flying-foxes is the blossom of eucalypts and some other native trees, and various bush fruits, like Moreton Bay Fig. The bats are beneficial to the trees because they act as pollinators and dispersers of their seeds. The great distances they can fly means they carry pollen and seeds far from the parent tree.

Camps are places where the large flying-foxes gather during the day, sometimes in many thousands. Along the coast they may be in mangroves, further inland they are often in deep gullies or rainforest patches, and west of the Dividing Range they are usually along water-courses. Their location may be known only to a few local people. The same campsites tend to be used year after year, although not necessarily every year, or all year round.

Damage to cultivated fruit varies greatly from one year to the next and between different areas. The factors controlling it are not well understood. Some areas rarely experience attacks, others do so most years. Widespread shortages of natural food, such as occur during droughts, may cause large numbers of animals to move well beyond their usual range in search of food. This applies particularly to Little Red Flying-foxes, which occur further inland than the other species.

Bats are the only group of mammals that are capable of powered flight. The scientific name for the group (Order) to which bats belong is Chiroptera that means 'winged hands', and gives an indication of the specialised adaptations that allow them to fly. Their 'winged hands', are greatly extended bones in their fore-limbs (our hand and arm bones) that are joined with a leathery membrane to form wings.

Bats wings have evolved to be very efficient in flight. As their wings are thinner than birds' wings, they are more maneuverable in flight. The membrane, which makes up the wing, is made of skin that is very soft, strong, flexible and able to repair itself if punctured. The thumbs of bats are left free from the wing, and they used it to groom themselves and cling to roosts.

The black flying fox was first described by Temminck in 1837 from a specimen from Menado, Indonesia. In 1867, Peters described a black flying fox from Rockhampton. The south-eastern limit of black flying-foxes has been moving southwards for at least 60 years. In 1930, the southern limit was Rockhampton and in 1960 it was the Tweed River, northern NSW. By 2002 they could be found further south than Port Macquarie.

The black flying fox is the largest of the four mainland species in terms of body size in Australia.

Description

Jet black fur but some variation does occur

Chocolate-brown patch of fur is often seen on the back of its neck and shoulders

Brownish fur around eyes and on face

Some have frosting of greyish tips all over their body, particularly on the belly

The lower leg is unfurred

Wingspan about 1m

Average weight of 500–1000g

Head–body length 230–280mm

Habitat

Wide range of habitats of tropical and subtropical forests and woodlands

Life history

Black flying-foxes can live up to 20 years in the wild.

Breeding

In southern Queensland adults mate in March and April, females become pregnant before dispersing for the winter months

Congregate into camps from early to late summer where the young are born and raised

Young are carried by the female until about 4 weeks of age and then left at the roost while the mother forages at night.

Young begin to fly at 8 weeks of age but depend on their mothers for at least 3 months.

Food

Fly out at dusk to feed on blossoms and fruits

Prefer blossom of eucalypts, paperbarks and turpentines, as well as a variety of other native and introduced blossom and fruits

Have been seen to eat the leaves of trees by chewing the leaves into a bolus, swallowing the liquid and then spitting out the fibre

Behaviour

During the day, black flying-foxes roost on tree branches in camps and fly out at dusk to feed.

Main camps form in summer and may contain tens to hundreds of thousands of individuals, depending on local food availability.

Can hold and manipulate food with clawed thumbs

They will wrap their wings around themselves if cold or wet.

Home range

Groups will travel up to 50km from their camps to foraging areas and will use the same camp for many years

Black Flying Fox Distribution in Australia

Distribution

Black flying-foxes are found around the northern coast of Australia and inland wherever permanent water is found in rivers.

The grey-headed flying fox was the first Australian flying fox species discovered by Europeans. The first grey-headed flying fox specimen was reported as collected in New Holland and described by Temminck in 1825. Their numbers have declined drastically since European colonisation from many millions to a few hundred thousand. The known range for grey-headed flying foxes has contracted southwards by about 750 km and their southern limit during winter has expanded into Victoria. They are the largest Australian fruit bat and are endemic to Australia. Grey-headed flying foxes have sophisticated vocal communication, making more than 30 specific calls.

Description

Grey-headed flying foxes are the only flying fox species with a collar of orange/brown fur that fully encircles the head

Grey-headed flying foxes are the only species with fur right down their legs to the toes

Average weight 600–1000g

Head–body length 230-290mm

Head covered in grey fur

Belly fur grey with flecks of white or ginger

Back fur can be dark grey or can have silver or frosted appearance (might be related to age/moult/subpopulation)

Little red flying-foxes are the most widespread species of megabats in Australia and the only species of Australian flying-fox that regularly roosts in clusters – up to 30 have been seen hanging together in a tight bunch. The weight of their clusters can cause severe damage to their roost trees.

Little red flying-foxes are nomadic and their movements depend on food resources. Peters first described the little red flying-fox in 1862, from a specimen collected on Cape York.

Description

Little red flying-foxes vary in colour from reddish brown to light brown, and there are patches of light, creamy, brown fur where the wing membrane and shoulder meet.

Head is covered with greyish fur and, in some forms found in northern Queensland, grey fur continues down the back.

Wings are brown and semi-transparent when seen flying during the day. This helps identify the species.

Average weight 300–600g it is the smallest flying fox in mainland Australia.

Head-body length 125–200mm

Habitat

Broad range of habitats that includes semi-arid areas to tropical and temperate eucalypt forests, paperbark swamps and monsoon forests

Breeding

Little red flying-foxes form large camps for mating that can include up to 100,000 individuals.

Mating occurs November–January, young are born in April and May.

Males have harems of two to five females in small, defended territories.

Young begin to fly at two months.

Female cares for young for several months while they develop the basic skills of finding food.

Food

Prefer nectar – especially eucalypt, bloodwood and angophera nectar.

Will eat fruit, sap and insects and cultivated fruit when other resources are unavailable.

Behaviour

In northern Australia, little red flying-foxes sometimes leave their roost sites before dark and feed during the day on overcast wet season days.

Often crash land in trees and need to climb a tree limb to take off again.

Efficient climbers that use their jointed thumbs as well as feet to climb about.

Prefer to roost near the ground.

Home range

Only travel 20–30km from camp to feed

Little Red Flying Fox Distribution in Australia

Distribution

Little red flying-foxes from Shark Bay in Western Australia round the north coast to Queensland and south to northern Victoria.

Have been recorded in South Australia.

As nomads they range a long distance inland, depending on the availability of flowering trees.

Threats

Habitat loss

Powerlines

Barbed-wire fences – little red flying-foxes fly low and are frequently caught on fences only a metre or so off the ground

Status

Listed as Lower Risk Least Concern according to the IUCN Red List of Threatened Species

Spectacled flying-foxes were first described in 1850 by Gould from a specimen collected on Fitzroy Island. They are important seed dispersers and pollinators of rainforest flora. Spectacled flying-foxes have the smallest known distribution and smallest population of the four Australian mainland Pteropus flying-foxes.

Description

Spectacled flying-foxes have distinctive straw-coloured fur around the eyes which gives them their name.

Black with pale yellow "spectacles"

Eye rings can sometimes be indistinct and they will look similar to black flying-foxes.

Pale fur on shoulders can vary between individuals.

Pale yellow fur often found on shoulders and back of neck

Average weight 500–1000g

Head–body length 220–240mm

Habitat

Tall rainforests, gallery forest, mangroves or paperbark forests.

Only in north Queensland

It is also found in New Guinea and on the offshore islands including Woodlark Island, Alcester Island, Kiriwina, and Halmahera.

Life history

Little is known about the life span of spectacled flying-foxes in the wild, but can live in captivity for 17 years.

Breeding

Mating common throughout first half of year but conception only in March–May, single young born October–December.